Sulfur nutrition of Puccinia graminis f. sp. tritici in axenic culture

Abstract

The amino acid requirements of subcultures of the wheat stem rust Puccinia graminis f. sp. tritici have been determined. These isolates will grow on an agar solidified medium containing Czapek's minerals, glucose, citrate, cysteine, and one of the following nitrogen sources: ammonium, aspartate, asparagine, glutamate, glutamine, alanine, serine, and glycine, but not nitrate or nitrite. Cysteine can be replaced by homocysteine or methionine, but not by inorganic forms of sulfur. Possible reasons for the requirement of these organic sulfur compounds are discussed.